This began as a response to
http://www.ozpolitic.com/forum/YaBB.pl?num=1377215387/0#0 which was, strangely, first posted to the "Politicians Suck" board. I reckon it's more appropriate in Environment.
NARRATIONHave you noticed anything odd round your place lately? A fish you've never caught before. Unusual events. Weird weather. Well, I've certainly noticed something odd round my home.
Dr Jonica NewbyI bought this place 12 years ago. And, in that whole time, it never flooded. Nor in the 20 years the old guy had it before me. In the last two years, it's flooded ten times.
NARRATIONI've pretty much stopped mopping. And, like many of us, as I survey the damage, I wonder if this is Climate Change, a rogue La Nina or just a really rainy year. Has the weather changed in the last 100 years or not? So, I'm heading on an investigation that's all about the simple facts. Real tidal gauges, actual temperature records. And this will be a proper weather report, going round Australia to the places you and I live and play. It's time to take the temperature of Australia. And, when it comes to weather, there's one organisation perfectly placed to guide me. They formed 100 years ago. They are the Bureau of Meteorology.
Dr Jonica NewbyHello, Karl.
Dr Karl BraganzaHow's it going, Jonica?
Dr Jonica NewbyGood. And... So you're going to run us through a national, 100-year Australia health check/weather report.
Dr Karl BraganzaThat's right. Today we're going to do a national round-up of Australia's temperature, hydration and its circulation.
Dr Jonica NewbyFantastic. So I reckon we start straightaway with temperature, which means I'm heading... here.
NARRATIONI don't want to start with the heat, but with the cold. Is it as cold as it used to be? And where better to view the cold than from our nation's frosty tips? Our enchanted, legendary snowy mountains... where I love to ski.
Dr Jonica NewbyYou may think me elitist, but I prefer to think it's the genetic imperative of my Norwegian ancestry.
NARRATIONAnd those Nordic genes of mine have a keen interest in what's happened to the snow.
Dr Jonica NewbyWell, this is 1964, the biggest dump on record. You look at photos like this, and you think things must have changed. But have they really? Is it anecdotal or real? To find out, you have to go to the records.
NARRATIONWe're off to Spencer's Creek, where the Snowy Hydro scheme has been taking snow-depth measures every week since 1954. Dr Ken Green has been monitoring the snow for decades.
Dr Kenneth GreenWe've got 65 inches, which...
Dr Jonica NewbyInches?!
Dr Kenneth GreenYes, inches. It's been done since 1954. So they're not going to change their methods now.
Dr Jonica Newby(Laughs)
Dr Kenneth GreenWhich is about... 162cm.
NARRATIONSnow cover swings wildly from year to year. So the best way to see the signal in the record is to compress it into five-year average trends.
Dr Jonica NewbySo, how are we going to do the trend line?
Dr Kenneth GreenWe'll put this in as the trend line.
NARRATIONHmm. In 60 years, we've lost a third of our total snow cover. But there is some rough comfort for my skiing aspirations. And that is that the beginning of the season hasn't really changed.
Dr Jonica NewbySo, basically, since 1954, snow depth in July is much the same. When you reach September, it starts to drop off. So that by October it's noticeably less. Essentially, spring is coming earlier.
NARRATIONIt's even clearer when you look at the records for the thaw, now two weeks earlier than in the '60s. And the snowline appears to have lately moved up from 1,500m to 1,600m.
Dr Kenneth GreenThis actually used to be a ski run, coming down here across the road. And now you wouldn't even dream of it.
NARRATIONSo what HAS happened to Australia's cold?
Dr Jonica NewbyRight. Our first national round-up. So we're looking at minimum temperatures. And, Karl, basically, this is how cold it gets at night.
Dr Karl BraganzaThat's correct, Jonica. If we start at the Snowy here, we've warmed by about 1.1 degrees since a century ago. And that's similar to Perth, Sydney. If we're looking over here at Cairns, it's almost 2 degrees since 1910.
Dr Jonica NewbyTwo degrees, so hot nights.
Dr Karl BraganzaWell, hotter nights than they used to have, yeah - on average.
NARRATIONAnd how do we know this to be true? Well, because, frankly, the data collection behind it is mind-boggling. This is the Victorian regional headquarters of the Bureau of Meteorology.
Dr Jonica NewbySo how many things are kind of feeding into all of this?
Kevin ParkynUm, too much, really for the brain to comprehend, to be honest. And that's why we have a lot of alerts that help us.
NARRATIONThere are nearly 800 weather stations across Australia, with over 500 now fully automated. Of these, 112 sites have information that historically goes back far enough and is accurate enough to count as blue-chip and be used as part of the 100-year record.
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